InfoPath Dev

Im using an SQL db.  I made a data connection with two tables.  I have a table with some fields: A_ContractID, A_ContractDate and A_CustomerID_Key.  Then I added another table with B_ContractID_Key. I also made a second data connection so I can populate dropdown list entries when the form loads.

I want to design a form using the second table's datafields.  I want to create a dropdown listbox for B_ContractID_Key which is populated from a external datasource.  I want the value to be B_ContractID_Key and the Display Name to be "A_CustomerID_Key - A_ContractDate".  So I can select a ContractID based on two other fields.  How can I do this?

I'd create a view in the SQL db that combines the two tables and use that as my data source for the drop down list. As you've noticed, you can only select one data source for a drop down's value / display pairs in IP, so a view or code will be the only way to do this....